Utilidad de la detección inmunocitoquímica de p16, en el diagnóstico diferencial de lesiones reactivas y neoplásicas en muestras de citología cervical.

Use of the immunocytochemical detection of p16 in the differential diagnosis of reactive and neoplastic lesions from cervical smear samples. Recently, p16INK4a has been identifi ed as a biomarker for neoplastic cervical lesions caused by HPV, and its presence has been proposed as a diagnostic tool for such lesions. Thus, the purpose of this study was to determine the use of the immunocytochemical detection of p16 in the specifi c and differential diagnosis of reactive and neoplastic lesions. A series of 40 cervical smear samples were used, including 21 cases negative for malignancy, 3 with ASCUS, 13 with low-grade squamous intraepithelial lesions (LSIL), and 3 with high-grade squamous intraepithelial lesions (HSIL). Only 20% of the cases showed overexpression of p16, with no signifi cant correlation with the cytological result. However, after matching cytological results with their respective histological diagnosis, 2 cases were found to be negative for malignancy, 32 LSIL (HPV and/or CIN-1), and 6 HSIL (CIN-2 and/or CIN-3). It was observed that the highest positive rate of p16 (67%) was in the cases with HSIL, while only 13% of the cases with LSIL were positive for pl6 immunostaining. This suggests that p16 can be used to confi rm the diagnosis in doubtful cases, and also help predicting the few cases with LSIL that have a higher risk of becoming HSIL and eventually invasive carcinoma.